The MIP Associated B6 17.5 Race Topshaft design has proven itself time and time again to be a winning formula. The B6 Series topshaft provides a 30% decrease in tooth width and an 18% weight reduction equating to less drag and less overall rotating mass when compared to its OEM counterpart. This ultra-light topshaft is made out of 7075-T6 aluminum and finished off with a premium strength high grade hard anodized coating.